Apron for wheeled scrapers



Mwch 8, 1949. K. E. REISCHL ET AL 2,463,559

AFPRON FOR WHEELED 'SCRAPERS Filed May 17, 1947 I 2 Sheets-Shet l e WWO; Jiwrdam,

, INVENTORS,

ATTORNEY March '8, 1949. K. E. REISCHL ETAL APRON FOR WHEELED SCRAPERS .2 Sheets-Sheet 2 Filed May 17, 1947 flu r6, fiubcM, a 7 rr'za uiddm,

INVENTORS, BY

I ATTwmEy Patented Mar. 8, 1949 APRON FOR WHEELED SCRAPERS Karl E. Reischl and George W. Mork, South Milwaukee, and Trevor 0. Davidson, Milwaukee, Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Dela- Wis., assignors to ware Application May 17, 1947, Serial No. 748,786

12 Claims. 1

Our invention relates to new and useful improvements in wheeled scrapers of the general type shown and described in U. S. Patent No. 2,321,410, granted June 8, 1943, to George W. Mork et al., to which patent reference is hereby made, inasmuch as this present invention represents an improvement thereon.

This is a continuation, as to all common subject matter, of our copending application, Serial No. 677,300, filed June 17, 1946, for improvements in Apron for wheeled scrapers.

In scrapers of the type mentioned above, the scraper fills and dumps at its front end.

The main frame of such a scraper is pivoted at either its front end or rear end to a wheeled truck, and the digging and spreading depth is determined by raising or lowering the other end with respect to a second truck. This is the first operating function.

In Mork and this present invention, the pivoting is at the front end, and the raising and lowerin takes place at the rear end; but this is not essential.

The digging blade is carried rigid with the main frame, though this is not essential.

Adjacent the digging blade is pivoted a dirtextruding curved member, variously termed. For conformity with the nomenclature of the Mork patent, it will here be called a. bucket. Swinging this bucket upward to dump is the second function. Returning this bucket to loadcarrying position is the third function.

There is also a front closure, known as the apron. Opening this apron (when digging or dumping), and closing it again for carrying, is the fourth function.

Mork has two controls (ropes), one of which performs the first function (namely depth-control), and the other of which successively performs the fourth function (apron opening) and the second function (dumping). For the third function (bowl return), Mork depends on a kick" back cam, actuated by the fall of the apron.

Our present invention is not concerned with the controls of these four functions, whether by one, two, three, or four ropes, or by an hydraulic cylinder or cylinders, or otherwise.

In the conventional scraper of the general type under discussion, the apron is opened a short distance for digging. and a considerable distance for dumping. The conventional opening for digging is fairly satisfactory; but, for dumping, the apron has to be raised excessively. high and even then still is nowhere near vertical, and so catches and holds the dirt being discharged by the bucket.

2 especially if this dirt be sticky material. Furthermore, even in digging position, it would be better if the apron were more horizontal.

Accordingly it is the principal object of our invention to provide an apron which will be more horizontal for digging; and yet which, for dumping, will open wider and more vertical than the conventional apron.

A further object is to provide means for breaking the sticky material in the apron, to facilitate dumping it.

A still further object is to provide means for readily converting our apron at will into a conventional apron.

In addition to our principal objects, above stated, we have worked out a number of novel and useful details, which will be readily evident as the description progresses.

Cur invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which two embodiments are exemplified in the accompanying drawings, which are hereinafter particularly described and explained.

Throughout the description, the same reference number is applied to the same member or to similar members.

Figure 1 is a vertical longitudinal'section of our scraper in carrying position.

Figure 2 is a similar section of our scraper in its highest digging position.

Figure 3 is a similar section of our scraper in dumping position.

Figure 4 is a portion of a similar section, showing a slight variation of our scraper, in the same position as Figure 3.

Referring now to the figures, we see that the implement to which we have applied our invention, includes a forward truck 2 l and a rear truck 22, supported respectively on forward wheels 23, and rear wheels 24. The forward truck 2! is rigidly secured to two side plates 25, preferably having substantially the outline indicated in the figures. In place of either such truck, we could support one end of the scraper on the propelling vehicle.

These parts constitute parts of the frame of the implement, and are connected together in .such a way as to enable the scraper blade 26,

which is located forward of the bucket 21, to be raised or lowered at will with respect to the ground level. In order to accomplish this, the rear truck 22 is preferably provided with rigid forwardly projecting side arms 28 that extend forwardly to a point about midway between the two trucks, at which point the arms 28 are connected by pivot bolts or pins 29 to the side plates.

Rigidly secured to the side plates 25, we provide a transverse lower beam 30, and an upper beam 3|, which latter beam may if desired be made of lighter construction than the lower beam. The inclined scraper blade 26 is preferably rigidly secured to the side plates 25, and cuts into the earth when the bucket 21 is being filled. Adjacent the blade 26 and preferably at its rear edge, the bucket 21 is pivotally mounted on a transverse pivot bar 33.

When the bucket '21 is in the position of rest. as indicated in Figure 1, the stop-bracket 34, carried by the rear face of the bucket, rests against a bumper or bumpers 35 on the top of lower beam 30, and this limits the downward movement of the bucket.

All the foregoing is conventional, and for the purposes of our invention is merely illustrative, inasmuch as our apron could be used with scrapers of quite different type.

We now come to the subject-matter of our invention, namely our apron. In place of the conventional apron, we employ the following. Our apron bottom is in two sections, one of which 36 is carried by conventional apron-arms 31 pivoted to the side plates 25, as at 38, and the other of which 39 is carried by a pair of auxiliary arms 49, which arms are pivoted to the arms 31, as at M, and to a pair of links 42, as at 43. Links 42 are in turn pivoted to the side plates 25, as by pin 44. Other means than links 42 could be employed to constrain auxiliary arms 40.

For simplicity in nomenclature, the following terminology will be used in our claims. Apronarms 31 will be referred to as apron-arms. Section 39 of the apron-bottom, plus auxiliary arms 40, will collectively be referred to as the apron. Section 36 of the apron-bottom will be referred to as an auxiliary apron section.

Now notice, in Figures 1 and 2, the relative position of the center-line of link 42 with respect to the dashed line from fixed pivot point 38 through fixed pivot point 44. In Figure 2 the center line of link 42 is exactly the same angular distance, 0, above the line 3B--44, that it is below it in Figure 1. The result of this is that in the position of Figure 2, as in -the position of Figure 1, the entire apron occupies a position exactly the same as though it were the convential apron of the prior art.

However, in between thOSe two positions, bottom section 39 is much more horizontal than in the conventional apron of the prior art. This feature of our invention prevents the loss of material during and immediately after digging. Furthermore, by properly altering the length of links 42, and their points of attachment to arms 49 and side plates '25, this feature of our invention can be extended to even wider opening.

In Figure 3, we have shown dotted, the comparative position which section 39 of a conventional prior-art apron would occupy with its apron arms rotated to the same height as ours. Note how much wider is the opening in our device, and how the apron bottom has even passed beyond vertical. and yet the apron lip hasnt been raised as high as in the prior art. All of which demonstrates that the prior-art apron, to open as wide as ours must have the center of gravity of the apron and associated parts much higher than ours (thus introducing instability), and even then wouldnt have as desirable an inclination and position of the bottom of the apron.

Without departing from the spirit of the lippositioning objective of our invention, section 36 of our apron bottom could be omitted, or could be carried by additional auxiliary arms as in the copending application of one of us, Trevor 0. Davidson, executed June 11, 1946 or the entire apron bottom could be carried by auxiliary arms 40, as apron bottom 39a of Figure 4. This will necessitate more arched arms 31a, and pivoting these arms to the outside rather than the inside of arms 40, all for the purpose of avoiding interference of parts. But to attain the dirtbreaking objective of our present invention, in addition to our lip-positioning objective, we prefer the arrangement as shown in Figures 1 to 3, or the arrangement which combines our invention with the said Davidson invention.

This dirt-breaking is accomplished by the relative angular motion of bottom sections 36 and 39 as the apron is raised.

Said Davidson invention and our present invention are in no sense alternative, being primarily directed to different objectives. For although our present invention does, to some extent, attain all of his objectives, yet his invention does not attain our primary objective.

In our claims, we shall refer to section 39 of our apron bottom (and likewise the entire apron bottom 39a of Figure 4) as an apron, and to section 36 of our apron bottom as an auxiliary apron section. By lip in our claims, we mean merely that edge of the apron which effects closure with the rest of the scraper.

As shown, the dumping rope 45 serves also to raise and lower the apron, as in the Mork application. The depth-control rope 46 is also shown. But the particular means for performing the four functions listed at the beginning of this specification forms no part of our invention.

And now to describe the convertibility feature of our invention.

Some operators may prefer the conventional apron for some sorts of digging, but certainly would not care to carry in stock both kinds of apron. However, if our apron could without alteration, and without the use of any more, fewer, or different parts, be rendered instantly and conveniently convertible from the hinged apron thus far described to the conventional apron of the prior art, and back again, this would be a very attractive feature.

This convertibility we have accomplished in a suprisingly simple manner, by merely boring a hole 44a (see Figures 2 and 3) in each arm 31 opposite the position occupied by pin 44 in Figure 1. Then conversion is effected, when our apron is in the closed position of Figure 1, by merely removing pins 44 from the holes in side-plates 25, and reinserting these pins in holes 44a in arms 31.

Thus altered, our apron now operates exactly like the conventional one-piece apron of the prior art, revolving as a whole about point 38 as a center, from the position of Figure 1 to the dotted position shown in Figure 3.

Reconversion can be as easily accomplished by restoring pins 44 to pivotal relationship with side-plates 25.

Having now described and illustrated two forms of our invention, we wish it to be understood that our invention is not to be limited to the specific form or arrangement of parts herein described and shown.

We claim:

1. In a carry-type earth-moving scraper, comprising digging means, a main frame, and dumping means, the combination, with said main frame, of a dirt-retaining apron, having a lip; means to raise the apron; apron-arms, pivoted to the apron, and pivoted on an axis fixed at all times with respect to the main frame, said axis lying to the rear of and distant from the pivotal connection between the arms and the apron; and constraining links, pivoted to the apron at points spaced from the pivotal connection between the arms and the apron, and pivoted on an axis fixed at all times with respect to the main frame, said axis lying to the rear of the pivotal connection between the links and the apron, and spaced from the first-mentioned axis.

2. A scraper according to claim 1, further characterized by the fact that the relative location of the pivot axes and pivotal connections, and the relative effective lengths of the arms and links, are such as, when the apron rises, to cause the apron lip to first be nearer to the pivot axis of the arms than in its lowest position, and then to be further from said pivot axis then in said lowest position.

3. A scraper according to claim 2, further characterized by the fact that the relative locations and lengths recited are such that the apron when slightly open is more horizontal, and when fully open is more vertical than as though it had rotated rigid with its arms.

4. A scraper according to claim 1, further characterized by the fact that the effective length of the links is shorter than the effective length of the arms.

5. A scraper according to claim 1, further characterized by the fact that the pivotal connections between the apron and the links are further from the apron-lip than are the pivotal connections between the apron and the arms.

6, A scraper according to claim 1, further characterized by the fact that each link is readily disconnectable at one of its pivotal connections, and that there is means for alternatively securing the apron rigidly to the apron arms.

7. A scraper according to claim 6, further char- 6 acterized by the fact that the readily disconnectable pivotal connection of each link is the connection at the fixed axis, and that the means for alternatively securing the apron rigidly to the apron-arms consists of means for connecting to the apron arms the link portion of this last-mentioned pivotal connection.

8. A scraper according to claim 1, further characterized by the facts that the effective length of the links is shorter than the effective length of the arms, and that the pivotal connections between the apron and the links are further from the apronlip than are the pivotal connections between the apron and the arms.

9. A scraper according to claim 1, further characterized by the fact that the relative locations of the pivot axes and pivotal connections, and the relative lengths of the arms and links, are such that the pivotal connections between the apron and the links lie below the plane of the two pivot axes when the apron is in its lowest position, and lie above said plane when the apron is in its highest position.

10. A scraper according to claim 9, further characterized by the fact that each link is readily disconnectable at one of its pivotal connections, and that there is means for alternatively securing the apron rigidly to the apron arms.

11. A scraper according to claim 10, further characterized by the fact that the readily disconnectable pivotal connection of each link is the connection at the fixed axis, and that the means for alternatively securing the apron rigidly to the apron-arms consists of means for connecting to the apron arms the link portion of this lastmentioned pivotal connection.

12. A scraper according to claim 1, further characterized by having an auxiliary apronsection rigid with the apron-arms, the apron and this auxiliary section together constituting a horizontally-jointed front closure for the scraper.

KARL E. REISCHL. GEORGE W. MORK. TREVOR 0'. DAVIDSON.

No references cited. 

